Textile sizing composition

ABSTRACT

A METHOD OF SIZING MAN-MADE YARNS, A NOVEL SIZING COMPOSITION AND NOVEL MIXING PROCEDURE FOR SAID SIZING COMPOSITION WHEREIN THE SIZING COMPOSITION COMPRISES A POLYVINYL ALCOHOL AND A POLYACRYLIC ACID.

Umted States Patent O 3,634,295 TEXTILE SIZING COMPOSITION Donald Thomas Dunlap and James Reid Misenheimer,

both Celanese Corporation, P.0. Box 1414, Charlotte, NC. 28201 No Drawing. Filed July 24, 1968, Ser. No. 747,079 Int. Cl. C0815 45/24 U.S. Cl. 26029.6 WB 2 Claims ABSTRACT OF THE DISCLOSURE A method of sizing man-made yarns, a novel sizing composition and a novel mixing procedure for said sizing composition wherein the sizing composition comprises a polyvinyl alcohol and a polyacrylic acid.

BACKGROUND OF THE INVENTION The methods and composition of this invention have particular utility in sizing polyamides such as nylon, polyesters, polyacrylics, cellulose acetate, cellulose triacetate and other man-made yarns, or yarns which are a combination of one or more man-made yarns, such as cellulose triacetate/nylon.

Sizing of yarns, usually called slashing, has as its primary object the adsorption and absorption of a filmforming material into and on the fibers comprising the yarn which may be in the form of hands or warps. This film-forming coating can be more or less continuous around the individual filaments, and is planned to secure the individual yarn filaments to the yarn bundle, to provide lubricity and to increase tensile strength and resistance to the abrasive action of the parts of the loom that are employed in the manufacturing of woven fabric from the yarn. Thus, adequate sizing results in increased weaving efficiency by reducing the number of breaks in the warp, clinging of the ends of the warp in the shedding motion of the loom, reduction of fiber shedding at the loom and facilitates proper operation of the stop motion and other functions of the loom. In addition, adequate sizing improves the quality of the fabric produced by reducing the number of fabric defects due to distortion of weave, knees, accumulation of excessive lint fiber or fuzz balls which are subsequently woven into the fabric, knots from excessive warp breaks, pull overs and filling floats.

The sizing process usually consists of passing the warp through a size box or trough containing a film-former, removing excessive film-former with squeeze rolls and drying over heated cylinders or in an oven. After drying the warp, the individual ends are separated from one another by a series of bars known as split rods or lease rods. A size which has little adhesion to the yarn will flake off or shed at the lease rods. On the other hand, a size which binds the yarn too firmly together will cause excessive end or yarn breakage.

The size warp, after separation at the lease rods, is wound on a loom beam then mounted on a loom and the individual ends drawn into the desired pattern.

The most widely used material for the sizing filmformer for yarn is starch because of its economy, ready availability in various ranges and effectiveness. It is particularly effective in the slashing of cotton, viscose and wool warps. The starch is usually added to cold water under agitation and agitating for 5 to 15 minutes to thoroughly disperse all the starch granules in the water. The resultant slurry is then heated until the starch is gelatinized. Softeners, plasticizers, penetrants, and other adhesive adjuncts may be added to the slurry prior to heating or after the starch has been cooked. The cooked Patented Jan. 11, 1972 sizing solution is then ready for transfer to the slasher after appropriate temperature adjustment.

With the introduction of various man-made fibers such as the polyamides, polyesters and polyacrylics, new sizlIlg problems were created. Adhesion of conventional starch sizing materials to these fibers was poor and major problems developed due to inadequately protected yarn resulting in low weaving efficiency and poor fabric quality. Similar results were obtained with yarns which were a combination of man-made fibers such as cellulose acelate or cellulose triacetate combined with nylon or polyester.

It is therefore a principal object of this invention to provide an improved method and composition for sizing man-made yarns.

More specifically, it is an object of this invention to provide an improved method of sizing man-made yarns, an improved sizing composition and a mixing procedure for a sizing composition which comprises polyvinyl alcohol and polyacrylic acid.

Further objects and advantages will be indicated in the following detailed specification.

SUMMARY OF THE INVENTION It has been discovered that man-made yarns may be effectively sized and adequate weaving protection maintained by utilizing a size composition comprising a polyacrylic acid and a polyvinyl alcohol. The use of such a size composition not only gives adequate weaving protection, but also greatly increases weaving efiiciency. In a preferred embodiment, the size composition is prepared by slurrying polyvinyl alcohol in water, preferably at a temperature of from about 10 degrees centigrade to 30 degrees centigrade for from about 10 to 20 minutes. Polyacrylic acid is then added and the mixture is preferably heated to from about 65 to degrees centigrade. Pine oil or its equivalent may be added to stabilize the size composition when the mixture will be stored for long periods of time prior to use. However, pine oil has no effect upon the function of the mixture as a size other than aiding somewhat in penetration and is not necessary to this invention. The mixture is preferably then cooked at a temperature of from about 75 degrees to degrees centigrade for from 20 to 40 minutes. Conventional agents such as flame retardants, softeners, penetrants, plasticizers, etc., may be added to the size composition.

It has heretofore been proposed to use polyvinyl alcohol alone as a sizing agent for various textile materials, especially nylon yarn. Polyvinylalcohol is a preferred material in this respect because it is water-soluble and, hence, easy to apply to the textile materials, and also because it does not corrode the equipment generally used in textile finishing operations. Despite its desirable properties, however, polyvinyl alcohol has an important drawback when used as such for sizing in that it does not adhere strongly enough to the yarn and, hence, has a sizing effect of relatively short duration.

Polyacrylic acid has also been suggested for use as a size composition. While it has been found that polyacrylic acid is superior to polyvinyl alcohol as a sizing agent, it too suffered from serious deficiencies, such as low weaving efficiency.

It is reported that when polyvinyl alcohol is combined with polyacrylic acid, the components of the mixture react to form an insoluble gel. However, we have discovered that these two inefiicient sizing agents can unexpectedly be combined to provide the improved size composition of this invention. The synergistic effect of the combination of polyvinyl alcohol and polyacrylic acid to yield a size composition which results in very high weaving efiiciency is unexpected. In a preferred embodiment, the ratio of polyvinyl alcohol to polyacrylic acid ranges from about 9:1 to 1:9, preferably from about 6:4 to 4:6, by weight.

Any desired type of polyvinyl alcohol of any convenient viscosity, such as from about 15 to 75 centipoises, may be employed in the practice of this invention. Polyvinyl alcohol is generally produced by the hydrolysis of polyvinyl acetate and either completely hydrolyzed or partly hydrolyzed products may be used. Polyvinyl alcohol having a degree of hydrolysis of from about 84 to about 100 percent, preferably from about 87.5 to about 99.5 percent, is especially useful.

The polyacrylic acid used may be any polyacrylic acid, preferably having a molecular weight of from about 25,000 to about 100,000. A suitable polyacrylic acid can be prepared by reacting acrylic acid monomer, a small proportion of a catalyst such as potassium sulfate and water.

The new sizing composition described above is effective for all man-made fibers and mixtures thereof with other man-made fibers. It may be advantageously used with synthetic fibers such as nylon, polyester, polyacrylic, cellulose acetate whether secondary acetate or triacetate, and the like. The composition is particularly adapted for the sizing of yarns which are a combination of cellulose acetate, cellulose triacetate and the like, and nylon, polyester and the like. These yarns may be blended or entangled by any available technique such as those disclosed in U.S. Pat. 2,673,442, to Long, issued Mar. 30, 1954, on an application filed June 2, 1952, and U.S. Pat. 3,110,151, to Bunting et al., issued Nov. 12, 1963, on an application filed May 26, 1961.

The sizing operation is advantageously carried out on a multi-can slasher wherein the cans are preferably maintained at temperatures of from about 60 degrees centigrade to about 100 degrees centigrade. The weight added to the yarn during sizing will vary depending upon the fibers in the yarn and the construction in which the fabric is to be woven. Usually, the weight of the yarn will be increased from about 2 to about 9 percent, preferably from about to about 7.5 percent.

Sizes prepared from the novel composition of this invention are characterized by uniform viscosity, absence of congealing and skinning properties, absence of foaming properties, good stability toward decomposition, high specific adhesion to the fibers and increased elasticity. As indicated previously, said size composition comprises polyvinyl alcohol and polyacrylic acid, with pine oil added as a stabilizer where storage for a long period of time prior to use is anticipated.

The invention will be more fully understood by reference to the following examples in which the parts given are by weight and the temperatures are in degrees centigrade, unless otherwise specified.

EMMPLE I Size preparation-43,608 grams of polyvinyl alcohol having a viscosity of about 25 centipoises and a degree of hydrolysis of about 89 percent was slurried in 60 gallons of water at room temperature for minutes. 14,150 grams of polyacrylic acid having a molecular weight of about 30,000 was added and the mixture heated with a steam coil to 74 degrees centigrade. 1361 grams of water-soluble pine oil was added and the mixture cooked at 88 degrees centigrade for 30 minutes. The volume of the size formulation was adjusted to 100 gallons.

Slashing.The above size composition was used in a conventional multi-can slasher to size a warp consisting of 4572 ends of a yarn consisting of 73 percent 55/15 cellulose triacetate and 27 percent /7 nylon 6,6. The temperature of the size was maintained at 60 degrees centigrade and the temperatures of the 5 cans of the slasher were maintained respectively at 71 degrees centigrade, 82 degrees centigrade, 90 degrees centigrade, 90

degrees centigrade and 71 degrees centigrade. The size take-up of the yarn on a bone-dry basis was 5.4 percent.

Weaving-The sized warp yarn described above was mounted on a loom and fabric was woven at a speed of 150 picks per minute. The pattern of the fabric construction was 88 ends per inch and 74 picks per inch on a 52- inch wide reed. 700 yards of material was woven and a total of two end breaks resulted. The weaving efiiciency was outstanding with less than 0.29 breaks per 100 yards of fabric Woven.

As a contol, cellulose triacetate/nylon 6,6 yarn was prepared in the same manner and woven into fabric in the same manner at a speed of 150 picks per pinute. 100 percent polyvinyl alcohol and 100 percent polyacrylic acid respectively were utilized as the size formulations. The weaving data for these fabrics as compared with fabric woven utilizing the polyvinyl alcohol/polyacrylic acid size formulation is shown below in Table I.

Size preparation-13,600 grams of polyvinyl alcohol having a viscosity of about 25 centipoises and a degree of hydrolysis of about 89 percent was slurried in 60' gallons of water at room temperature for 15 minutes. 14,150 grams of polyacrylic acid having a molecular weight of about 30,000 was added and the mixture heated to 77 degrees centigrade. 1360 grams of water-soluble pine oil was added and the mixture cooked at 88 degrees centigrade for 30 minutes. The volume of the size formulation was adjusted to 100 gallons.

Slashing.The above size composition was used in a conventional multi-can slasher to size a warp cOnSisting of 71.5 percent 100/26 cellulose secondary acetate and 28.5 percent 40/13 nylon 6,6. The temperature of the size was maintained at 60 degrees centigrade and the temperatures of the 5 cans of the slasher were maintained respectively at 71 degrees centigrade, 82 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade and 71 degrees centigrade. The size take-up of the yarn on a bone-dry basis was about 5.5 percent.

Weaving.The sized warp yarn described above was mounted on a loom and fabric was woven at a speed of 156 picks per minute. The pattern of the fabric was 92 ends per inch and 56 picks per inch on a 49-inch wide reed. 480 yards of material was woven and a total of one end break resulted. The weaving efiiciency was outstanding with less than 0.21 breaks per yards of fabric woyen and 0.00 pullovers.

As a control, cellulose secondary acetate/nylon 6,6 was prepared in the same manner and woven into fabric in the same manner at a speed of picks per minute. Polyvinyl alcohol was utilized as the size composition. 475 yards of material was woven and a total of two end breaks resulted, i.e., 0.42 warp breaks per 100 yards of fabric woven.

EXAMPLE III Size preparation.13,600 grams of polyvinyl alcohol having a viscosity of about 25 centipoises and a degree of hydrolysis of about 89 percent was slurried in 60 gallons of water at room temperature for 15 minutes. 14,150 grams of polyacrylic acid having a molecular weight of about 30,000 was added and the mixture heated with a steam coil to 74 degrees centigrade. The mixture was then cooked at 88 degrees centigrade for 30 minutes. The volume of the size formulation was adjusted to 100 gallons.

Slashing.The above size composition was used in a multi-can slasher to size a warp consisting of 4570 ends of a yarn consisting of 75/LTDZ/ 20 cellulose triacetate. The temperature of the size was maintained at 55 degrees centigrade and the temperatures of the 7 cans of the slasher Were maintained respectively at 70 degrees centigrade, 82 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade, 82 degrees centigrade and 65 degrees centigrade. The size take-up of the yarn on a bone-dry basis was about 5.5 percent.

Weaving.-The sized warp yarn described above was mounted on a loom and fabric was woven at a speed of 150 picks per minute. The pattern of the fabric construction was 96 ends per inch and 62 picks per inch on a 52-inch wide reed.

EXAMPLE IV Size preparation-19,425 grams of polyvinyl alcohol having a viscosity of about 25 centipoises and a degree of hydrolysis of about 90 percent was slurried in 60 gallons of water at room temperature for 15 minutes. 8,325 grams of polyacrylic acid having a molecular Weight of about 30,000 was added and the mixture heated to 75 degrees centigrade. 1,360 grams of water-soluble pine oil was added and the mixture cooked at 88 degrees centigrade for 30 minutes. The volume of the size formulation was adjusted to 100 gallons.

Slashing.The above size composition was used in a conventional multi can slasher to size a warp consisting of 71.4 percent 100/26 cellulose triacetate with 28.6 percent 40/13 nylon 6,6. The temperature of the size was maintained at 60 degrees centigrade and the temperatures of the cans of the slasher were maintained respectively at 71 degrees centigrade, 82 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade and 71 degrees centigrade. The size take-up of the yarn on a bone-dry basis was'about 5.5 percent.

Weaving-The sized warp yarn described above was mounted on a loom and fabric was woven at a speed of 156 picks per minute. The pattern of the fabric was 90 ends per inch and 74 picks per inch on a 52-inch wide reed.

EXAMPLE V Size preparation.--13,608 grams of polyvinyl alcohol having a viscosity of about 25 centipoises and a degree of hydrolysis of about 89 percent was slurried in 60 gallons of water at room temperature for 15 minutes. 14,150 grams of polyacrylic acid having a molecular weight of about 30,000 was added and the mixture heated with a steam coil to 74 degrees centigrade. 1361 grams of water-soluble pine oil was added and the mixture cooked at 88 degrees centigrade for 30 minutes. The volume of the size formulation was adjusted to 100 gallons.

Slashing.The above size composition was used in a conventional multi-can slasher to size a warp consisting of 4570 ends of a plied yarn consisting of 55/ 15 cellulose triacetate. The temperature of the size was maintained at 55 degrees centigrade and the temperatures of the 5 cans of the slasher were maintained respectively at 71 degrees centigrade, 82 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade, 90 degrees centigrade, 82 degrees centigrade and degrees centigrade. The size take-up of the yarn on a bone-dry basis was 5.5 percent.

Weaving.The size warp yarn described above was mounted on a loom and fabric was woven at a speed of 150 picks per minute. The pattern of the fabric construction was 96 ends per inch and 62 picks per inch on a 52-inch wide reed. 492 yards of material was woven and a total of 7 end breaks resulted. The weaving efliciency was outstanding with less than 1.4 breaks per 100 yards of fabric woven, as compared with the normal average of 2.5 breaks per 100 yards.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for preparing a yarn size composition which comprises slurrying polyvinyl alcohol in water at a temperature of from about 10 degrees centigrade to about 30 degrees centigrade for from about 10 to 20 minutes, adding polyacrylic acid having a molecular weight of from about 25,000 to about 100,000 and heating the mixture to a temperature from about 65 degrees centigrade to about degrees centigrade, adding a penetrant and/or stabilizer prior to cooking, then cooking the mixture at a temperature of from about 75 degrees to about degrees centigrade for from about 20 to about 40 minutes.

2. The process of claim 1 wherein prior to cooking, water-soluble pine oil is added as a stabilizer.

References Cited UNITED STATES PATENTS 2,557,266 6/1951 Dittmar et a1. 260874 X 2,609,350 9/1952 Spatt 26029.6 WU 2,845,689 8/1958 Renold et al. 26029.6 WU UX 2,850,471 9/1958 Klein 26029.6 WU X 3,133,865 5/1964 Richardson 26029.6 WU X 3,365,408 1/1968 OHara 26029.6 WU

OTHER REFERENCES Wise and Jahn, Wood Chemistry, 2nd ed., Reinhold Press, 1952, p. 577, lines 6-10.

JULIUS FROME, Primary Examiner D. A. JACKSON, Assistant Examiner US. Cl. X.R. 260874 72w UNTTED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, Dated January 11,

Inventor(s) Donald Thomas Dunlap, James Reid Misenheimer It is certified that error appears in the above-identified'patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 5, following "28201" insert assignors to Celanese Corporation, New York, New York.--

Column 4, line 11, "contol" should be control-- Table I, line 24 "acip" should be -acid- Column 4, line 60, "Polv" should be --Poly- Signed and seeled this 8th day of August 1972.

( SEAL) Attsst:

EDWARD M.FLETCI-IER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

